Germinal center entry not selection of B cells is controlled by peptide-MHCII complex density

Abstract

It has been thought that germinal center (GC) B cells with the highest density of peptide-MHCII molecules receive the most T cell help. Here the authors use heterozygous MHCII inactivation to instead show that after recruitment into the GCs, BCR affinity increases over time independent of the MHC density.